A good client for noobs is Phoca95. It isn't as powerfull as RoAClient or a registered verision of ZMUD, but it's simple to use and effective. Plus, with the author working on a new version for XP, he's made commercial version of 95 available for free!

If your already using another client and like it, downloading this is probably a waste of time for you. However, if your still looking for a client, it may scratch your MUD itch.